JP

[VsteveV]

Santa ( AKA: wife) is going to bring/allow me to get a JP for my 18RF. I'm looking for feed back on what set back I should get and Atlas or Bobs?

[Lap it Up]

I prefer Bobs. Great product. 

[JEM]

This question comes up a lot.  It seems more boat manufacturers use Atlas, supposedly because they get them at a better price than other makes.  However, when the boat owners are asked, Bob's seems to be the preferred jack plate.  I had a Atlas jp installed on my 2007 Path 2200V this past March, and don't have any complaints with about 60 hours use.  From what I read, owners like the Bob's because it is faster than an Atlas, but I am not sure what other advantages it has over the Atlas.  For me, reliability would be the determining factor on which to buy.  Now, if you can determine which is more reliable.........

[mulligan]

 Now, if you can determine which is more reliable.........

 

I have never owned an Atlas but my Bob's is almost 12y.o.,pump lives in the bilge area of my boat and has only had to have a solenoid replaced. ($15).  So I would say Bob's is pretty reliable. 

[geeviam]

I installed an Atlas JP on my Redfisher 16, and I like it very much.  It is smooth and fast.  I cannot testify to long term reliability because I just got it in October of this year.  I tried the CMC Power-Lift HS beforehand, but sent it back because of problems with one of the rollers binding and galling.
My setup is non-standard but works for me.  My boat had a cavitation issue and was breaking loose on turns with every prop I tried.  I needed to get the prop lower and further back into cleaner water with less turbulence.  However, the thing about jack plates is that they all have about 1" or more of lift built-in, even when they are all the way down.  So, my setup consists of an Atlas 4" JP plus a set of CMC 2.5" static setback plates plus a set of CMC 2-degree transom wedges between the setback and JP (pictured below).  This kept the engine mount bolts at about the same height as they were on the transom, because the CMC setback plate allowed me to drop the JP down by one hole (about 3/4" lower).  I can still tilt the motor up with the JP all the way down for proper towing too (actuator at rest).
Yes, the back of the boat squats a little more with the 4-stroke 115 hanging further back, but the performance gains are worth it.  Only 4% prop slip now and it's not breaking loose in turns.

 

 

 

[lurem]

Very clean look Geeviam! I like it!!

[geeviam]

2 hours ago, lurem said:

Very clean look Geeviam! I like it!!

Thanks DC

[mulligan]

Geeviam

Did you try the JP without the 2.5 spacers?  Only reason I ask is that I have been kicking around the idea of spacers on my boat.

[geeviam]

21 minutes ago, mulligan said:

Geeviam

Did you try the JP without the 2.5 spacers?  Only reason I ask is that I have been kicking around the idea of spacers on my boat.

No, I did not.  Both, the CMC and Atlas JPs, were only tested with the 2.5" spacers.  The spacers were the only way to get the motor cavitation plate down closer to the keel line (using the existing holes in the transom) and also have the clearance to tilt the motor without having to raise the JP.

[geeviam]

Here's a couple pics of the 2.5" spacers:

[mulligan]

Gotcha, thanks.

[linesider 159]

I've had 4 bobs and 2 atlas plates. I will always buy bobs. I hated both of my atlas plates. I ended up just greasing the slides on one of the Atlas because the pump wasn't strong enough. 

By the time the Atlas fully raises the sun seems to be setting. Only kidding of course, but the difference in speed is very noticeable.

My most recent bobs was the 10 inch action jack powder coated black. Loved that plate 

[geeviam]

I have no doubt that Bob's builds a good JP.  I wanted a Bob's JP - it was the first JP that I ordered for this boat.  I ordered it online with my credit card, added 2-day express shipping for faster delivery, got an order confirmation including confirmation that a shipment was scheduled to arrive in 3 days.  Called them the next day to see if I could add a hole-shot plate to the order and happened to find out that the jack plate was back-ordered and would not be shipped for 4 weeks.  Now, most companies do not charge payment to your credit card until an item is shipped.  They might authorize the card, but they don't finalize payment.  Bob's created a shipping label ( tracking # and confirmation that it was shipped) the day I ordered it and finalized the transaction on my credit card, knowing that the JP would not be built for 4 weeks.  That didn't sit well with me but I went along and waited for it to be shipped.  When it had not been shipped after 5 weeks, I called and cancelled the order because I could not wait any longer.  Bob's refunded my money and I bought my CMC and Atlas JPs elsewhere (in stock and on time).  It worked out better for me anyway because Bob's does not offer the Action in less than 6" setback and I wanted to use the CMC 2.5" spacer for reasons stated in previous post.  So far I am happy with the decision.

[VsteveV]

So Bob's seems to be the one to get, plus I live in Tampa so that works out. What about set back? Looks as if the 6" self contained is the way to go? Or do I need to look at the 4"?

[Lap it Up]

6" works just fine for me.  1998 RF 18

[VsteveV]

I finally got the JP 6" Bob's on last week and made a few trips out. I have to say that the performance is not what I expected and quite frankly, the hole shot feels a little worse. I feel (and hear) what seems to be slippage and the prop breaks free easily on hard turns if I have it raised slightly. The sound, to me, seems to be the prop venting cause the RPM's spike. Porpoising seems a little worse and even a full throttle take off causes the bow to rise quite a bit. I'm relying on the tabs, A LOT.  My only thought is the vented prop might be causing it? Motor is mounted on the lowest setting mounted to the JP and it appears that the motor would have been the middle hole if mounted back directly to the transom .I have a PT SCD17 with 3/8 ports and the prop was completely refurbished fall of 2016. Maybe a new prop?  Looking for some opinions on what I might be able to do before I consider removal. Motor is the F115.            

[geeviam]

12 hours ago, VsteveV said:

I finally got the JP 6" Bob's on last week and made a few trips out. I have to say that the performance is not what I expected and quite frankly, the hole shot feels a little worse. I feel (and hear) what seems to be slippage and the prop breaks free easily on hard turns if I have it raised slightly. The sound, to me, seems to be the prop venting cause the RPM's spike. Porpoising seems a little worse and even a full throttle take off causes the bow to rise quite a bit. I'm relying on the tabs, A LOT.  My only thought is the vented prop might be causing it? Motor is mounted on the lowest setting mounted to the JP and it appears that the motor would have been the middle hole if mounted back directly to the transom .I have a PT SCD17 with 3/8 ports and the prop was completely refurbished fall of 2016. Maybe a new prop?  Looking for some opinions on what I might be able to do before I consider removal. Motor is the F115.            

VsteveV,

When you get a chance, maybe you could post a picture of your JP & Motor mount setup.  I've done a lot of testing on my RF 16 and determined that I should have ordered it with a 22" shaft motor (haha), if there was a possibility that I would be installing a Bobs or Atlas 6" jack plate.  Even with all the tweaks, spacers and height adjustments, the prop still breaks loose in turns if the motor and JP are not trimmed all the way down (with tabs up).  The transom is just too tall to accommodate the additional 1.5" to 2" of motor height that comes with these particular jack plates.  Dale Carter (Lurem) installed a 4" Atlas Micro-Jacker JP on his 2007 RF 16 and it seems to be working well for him.  The Micro-Jacker has close to zero motor lift built in, when the JP is all the way down.

[VsteveV]

 

 

 

 

[geeviam]

Man, that's a good looking jack plate!  However, I think that extra 1.5" of motor height is going to cause a propeller ventilation problem that will not be easily fixed.  You could try some different props and see what happens?  Marcus at PowerTech (Funky Monkey on this board) might have some ideas.  He is very good at propeller setup on a Hewes.

[lurem]

Also, the SCD prop does not like to be trimmed.  It runs best trimmed all the way in to maybe out one bar. Forum member Mulligan had good luck with his SCD by sending it out and having some cup added.

[VsteveV]

I see RF's come from the dealer equipped with the same plate, only its at atlas, so I can't imagine my issue is unique.  Feedback appreciated cause this is going to drive me nuts.

[savvy]

I recently purchased an '01 18 RF in excellent condition w/ a 150hp, but w/o a jack plate. Brought it home one afternoon, and dropped it off at the shop the next morning for some add-on accessories, including a 6" bob's jp. Never ran it before, but after the jp was installed, the boat planes quickly w/o blowing out up to the 2" setting on the jp, above that it blows out consistently but still gets on plane; the same applies with cornering and turning. Have no idea what prop is on it; there are no stamped markings and it's a 60 mph boat, so I assume it's the right prop. I previously owned an '04 PF w/ a 200hp and the same 6" jp; it would blow out with any lift on it, so I assume the RF taking off on the 2" setting is pretty good. No idea what length motor shaft is on my RF; it looks like the longer shaft motor though.

[geeviam]

1 hour ago, VsteveV said:

I see RF's come from the dealer equipped with the same plate, only its at atlas, so I can't imagine my issue is unique.  Feedback appreciated cause this is going to drive me nuts.

Here are a couple of video links from Capt Drew Cavanaugh, showing the Redfisher 16 features and well as some hole-shot and running demos.  He has a 6" Atlas JP (factory rigged I think) on his boat.  It looks to me like his motor mount holes were drilled about 1/4" lower than normal on his transom.  Sometimes, a quarter inch can make a difference on prop ventilation.  Also, you'll notice he is using the same SCD prop that you are and he doesn't trim his motor up with power tilt at all - even at high speed.  That's because Lurem is right - those props don't like to be trimmed up.  I tested the SCD when I first got my boat and had the same results - could not trim up without losing grip, even before I installed the JP.  I lost grip in turns with every prop I tested back then - until I tried the Merc SpitFire X7.  Mercury pushed the limits of cupping with the design of that prop.  Also, one more thing - all the Redfisher 18s that I have seen with a 6" Atlas JP, had a Yamaha F150 hanging on them.  That's quite a bit more weight than your F115, which drops the stern and the prop lower in the water for better grip.  Hope this helps you.

 

[VsteveV]

The examples are with max hp. I still have a few years left before I can consider a repower. Would it be possible, or advisable to drill new mount holes on the plate? And the rf16 has 5/16 ports while I have 3/8. 

[mulligan]

Lurem is right.  I ran a SCD that was tweaked with some cup.  I did held greatly with grip and performance and I was able to trim to the moon without it breaking free.  Are you fully trimmed in on holeshot?  The only reason I ask is you said you have a lot of bow rise.  The SCD is a semi-cleaver for stern lift and you should have about as flat as a holeshot as possible. If you are having bad ventilation on your holeshot you can plug the holes to see if that helps, 3/8 seem to be on the large side, mine had no vents.